


Your Light Has Changed

by pentaceratopsian



Category: Kingdom Hearts
Genre: Alternate Universe - Canon Divergence, Fix-It, Hurt/Comfort, Multi, Polyamory Negotiations, Post-Traumatic Stress Disorder - PTSD, cheesy and self indulgent as god intended, post-kh3
Language: English
Status: In-Progress
Published: 2019-04-10
Updated: 2019-04-10
Packaged: 2020-01-11 05:11:16
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,714
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18423540
Author URL: https://archiveofourown.org/users/pentaceratopsian/pseuds/pentaceratopsian
Summary: During the final confrontation with Xehanort, Kairi is faced with a difficult choice. The outcome is something no one would have ever thought possible and she gains a powerful new set of skills. Kairi must learn to grapple with her terrifying new abilities before her power overtakes her. Sora and Riku, despite their efforts, aren't helping matters. Post-KH3. Canon divergence from the very end of the game. Spoilers for KH3, obviously.





	1. Chapter 1

Xehanort chuckled and lifted the unconscious girl off the ground with his dark magic. She floated her into view of the group below him.

Sora knew instantly. He gasped. “Kairi!”

“You require… motivation,” Xehanort said.

He had to stop him! Sora ran up the cliff as fast as he could, but he would not make it in time. Xehanort lifted his keyblade high behind him and moved to strike her in the back. This was meant to be a killing blow, done so viciously as to _shatter_ her entirely. There would be no release of her heart. This was a murder.

The blow made contact between her shoulders. She made a tiny noise and was surrounded by purple light. He grinned villainously. Everything was to plan, and he would get that thirtheenth key and end this decades-long charade at last.

But something happened. Something no one, not even Xehanort, grand master of convoluted plans, could anticipate. Instead of shattering the girl, the purple light intensified and deepened in color, going darker and darker until it was pitch black. She was engulfed in a ball of pure darkness.

“What-?!”  
  
The dark ball exploded, sending Xehanort flying back several feet. He landed flat on his back.

“Kairi!!”

Xehanort sat up in confusion just as Sora reached the top of the ledge, primed to strike him down, keyblade drawn and held aloft. When he comprehended what was before him, he dropped the keyblade instead. His intended soft landing became a pathetic fall to his knees.

There, hovering inches above the ground, was a Heartless shaped just like Kairi. Dark energy radiated off of her like evil black sun rays. Her eyes glowed bright yellow. She had her own keyblade drawn, but it looked all wrong. It was black and red instead of pink and yellow. She turned toward Xehanort, ignoring Sora for the time being.

Xehanort began to wheeze through laughter.

“What did you DO to her?!” Sora drew his keyblade once again.

“Me, boy? I didn’t do a thing! This is _her_ _own_ doing! It seems your princess lost her light!” He cackled again. “An unforeseen occurrence, but not one that will impede my success.” He stood and dusted himself off.

Kairi’s Heartless snarled and leapt toward him. He moved to dodge her advance, but was not prepared for her to disappear. She teleported just above him and brought down a series of blows with her dark keyblade. She slashed and slashed viciously, and he took every hit with a grunt. She moved blindingly fast.

Sora watched this all unfold slack-jawed, awed and terrified of his best friend all at once. The barrage went on for a solid two minutes, _much_ longer than anyone else had been able to get with Xehanort or one of his lackies that day, before he finally righted himself and got the upper hand again.

“That’s quite enough,” he cried. He managed to knock the raging feral Kairi heartless away.

“This can’t be right. This can’t be happening… this can’t be you! Kairi! KAIRI!”

Her head snapped toward Sora. Tears ran down his face. He reached out for her. He trembled, sure that he might fall over at any moment.

Kairi’s glowing eyes narrowed. She rushed towards him.

“What? No! Kairi, stop! KAIRI!”

 Xehanort laughed once again. She jumped into the air and reared back, ready to strike Sora down. He made no movement to defend himself.

“Please--!”

He squeezed his eyes shut, preparing for the blow. But it never came. Instead, he heard a loud _clank_ and a grunt in Riku’s voice. He opened his eyes again to the sight of Riku shielding him, blocking Kairi with his keyblade. Ahead of them, Mickey had surged forward to attack Xehanort with light magic. Kingdom Hearts shone ominously above them.

“That’s enough!” shouted Riku. “You aren’t going to hurt Sora. Come back to your senses!”

Red and black tendrils of dark energy flared from her and she began to swing wildly at Riku, continuing to shield himself and Sora all the while. In anger, he managed to push her away with his keyblade. She floated backwards, then back down, coming to rest in a hovering battle stance pointed right at Sora and Riku.

“Kairi,” Sora whimpered. He began to sob. “Come… back to us.”

 It was like he’d recited magic words. Suddenly, the darkness started to break away from Kairi. It looked to be melting off of her, then pouring off of her, then simply dissipating in streams of light. She gently landed on her feet, eyes closed.

“Kairi!” Sora and Riku shouted in unison. She opened her eyes and rubbed her forehead.

“What—"

The two boys bolted to her and crushed her in a tight group hug. Sora continued to cry.

“Kairi, you’re okay!” Sora squeezed as tight as he could.

 "Ultima!”

“Stopza!”

The boys broke their embrace and the trio turned abruptly to face the battle going on behind them. They froze in place mid-movement. Mickey was frozen in midair. From behind the group, a keyblade rose up and glided over to Xehanort. He cackled. Everything was in place now.

“Now… the keyblade war will finally reach its conclusion!”

When the world started moving again for Sora, Riku, Kairi, and Mickey, Kingdom Hearts was shrouded in pure darkness and dark energy rained from the sky. Xehanort hovered high above, so far up they could barely see him. They were surrounded by their friends, the other Guardians of Light.

“It’s over,” Sora said quietly. Horrorstruck. “We lost.”

Neither Riku or Kairi knew what to say. Riku looked to Mickey, hoping he would have an answer, but the mouse scratched his head and stared at the ground, brow furrowed. His eyes suddenly widened.

“I’ve got it! Fellas, we’ve still got hope! Riku, do you remember what we learned about Xehanort during your mark of mastery exam?”

“Huh? Oh! Do you mean—”

The two went on to explain Xehanort’s ability to time travel and formulated a plan to stop him. Sora, ever the self-sacrificing adventurer, enthusiastically volunteered to travel back in time and stop Xehanort once and for all.

“I need all of you to stay here and keep Kingdom Hearts open!”

Everyone, in turn, nodded in agreement with Sora’s plan. All except for Kairi. Kairi stood staring at her trembling hands, tears welling in her eyes. Sora took those hands in his.

“Kairi… are you going to be okay?”

She met his gaze.

“I… I’m terrified. What was that? What if it happens again?” Her voice barely registered above a whisper. Sora frowned.

“I know what it was,” said Riku. “At least, I’m pretty sure I do. Kairi, somehow, there’s darkness in your heart now. When Xehanort moved to strike you down, that darkness came surging forward. It was protective instinct. I’ve seen the same thing happen to Sora before when battles got desperate.”

“Right… my anti-form,” said Sora.

“I know what that dark rush feels like even better than he does. I could recognize it a mile away. It’s scary, but I promise, you’re going to be okay.” Riku put his hand on her shoulder and gave it a squeeze.

“…She was right,” Kairi whispered. Hot tears welled over, her face crinkled into a grimace, and she let out a sob.

 “Huh?”

Kairi shook her head, then wiped away her tears. “Never mind. More… importantly,” she said, choking back another sob, “Sora… what will I do if I lose _you_?”

That was enough to make Sora start crying again, but he forced his face into a teary grin.

“You worry too much, Kai,” he said with a cracking voice. “I always come back in one piece!”

“He’s right,” said Riku softly. “Sora makes the impossible possible.”

Sora put his arms behind his head. “I try!”

Kairi laughed in spite of herself.

“Kairi, I promise you that I’ll come back to you. In the meantime, Riku is going to take care of you while we’re up there fighting. Right, Riku?”

Riku nodded.

Kairi bit her lip and nodded too. “Be safe.”

And the guardians gathered one last time to unlock Sora’s way to Xehanort’s point of origin.

**Notes for the Chapter:**

> Hi everybody! Thanks for coming to my TED talk on Why My Girl Should Be Treated Better By Her Creators!
> 
> I started writing this back in January almost immediately after I finished the game. The ending left me sobbing in my girlfriend's lap because I was so angry and sad I didn't know what else to do with myself. So I fixed it! I'm not as angry or sad anymore, but I do still think the way they handled Kairi was horseshit. This fic is mainly my attempt to do her a little better than Square did themselves.
> 
> Because I know myself well enough by now, I thought I'd try something a little different with this fic and wait until it was fully finished to start uploading it. I've split the thing into chapters and intend to post one or two a week until it's all up, with the first two chapters being posted today. Let's see how this goes!
> 
> Special shout out to my panel of friends (you know who you are) for reading this and helping me revise it. I couldn't have done it without y'all. And to you, the fine readers, I hope you enjoy this as much as I do.


	2. Chapter 2

**Summary for the Chapter:**

> Sora, Riku, and Kairi return to the islands. Everyone's doing okay, for the most part, except for one teensy little problem: Kairi's darkness. Sora and Riku start some investigating while Kairi encounters a foe...

Xehanort, at long last, was defeated. The universe was saved. Sora, Riku, and Kairi returned permanently to the Destiny Islands. Finally, they were really and truly _together_ , ready to take on the future! Everything was going great, except that Kairi didn’t talk about what happened that day again. Any time Sora or Riku would try to bring it up, she would change the topic. Eventually, they stopped trying. They noticed her occasionally with a dark, angry look when she thought no one was watching.

One day, shortly after the battle had concluded, Sora and Riku got together at the beach on the main island and decided to call Ienzo for his advice. He, being a scientist, would _probably_ understand what was going on, right?

"Sora! Riku! What an unexpected surprise.”

“Hi Ienzo! How’s the science stuff?”

Ienzo chuckled. “Illuminating. We’re learning so much! You really ought to visit us soon.” There was a loud crash, a yelp, and bang behind him that caused all three to startle.

“Sorry!” yelled a distant voice. Ienzo rolled his eyes, shook his head, and sighed.

“Hey, that sounded like that weird music guy!”

“That’s because it is,” Ienzo said. “Demyx joined our side before the battle along with Even and Master Ansem. They’ve been with us ever since.”

“WHAT?!” Sora and Riku cried in unison.

“Demyx? A _scientist_?! And Master Ansem is _alive?!_ That can’t be right,” said Sora.

“That’s exactly what I thought when it happened,” said Ienzo, “yet, without them, I don’t think we would’ve won that battle. And we’re all grateful to you three as well. We’re glad to have been able to contribute in our own small way. I’m sorry we weren’t able to do more.”

“Don’t sell yourselves short,” said Riku. “You were just as important.”

Ienzo smiled.

“Ienzo, we’re calling you because we want to pick your brain,” said Sora.

“Certainly! What’s your question?”

Sora and Riku took turns explaining the situation with Kairi during the final battle and in the following days. Ienzo made _ah_ ’s, _oh_ ’s, and _wow_ ’s throughout.

“This is _fascinating_! I never knew such a thing could happen!” He rubbed his chin.

“Neither did we,” said Riku. “Kairi is a Princess of Heart. This shouldn’t be possible.”

“Indeed, and yet it happened. I suppose by now we should all know to expect the unexpected. This reminds me of the situation with Naminé. By all accounts, _she_ should not have been able to exist either.”

“That’s right,” said Sora. “Do you think when Naminé was created some of my heart’s darkness stuck around in Kairi’s?”

“That could be a possibility. But Kairi retained her connection to the light after the events of your first adventure while the other princesses passed it on. So that darkness couldn’t have _survived_ in her heart, at least not that long.”

Sora scratched his head and looked at the sky in thought for a moment. He groaned and slumped.

“How can we help her if we can’t ever figure this out?! I’m so confused,” he whined.

“Wait a second,” said Riku. “The other princesses gave up their lights so new protectors could watch over them. And you said Kairi never did, right?”

“That’s what we assumed,” said Ienzo.

“And princesses have the ability to do this willingly? Consciously?”

“I… suppose? We didn’t get that far into researching her heart and the hearts of princesses; all we knew is that their hearts contained pure light. I’m deeply sorry about that, by the way. There is no way to atone.”

Riku shook his head and handwaved his concern away. “What if they can _sense_ when they need to give it up to someone else and could make that choice? Or... what if it's not actually a choice at all?”

Ienzo’s eyes widened. “You’re suggesting that--”

“Kairi let it go,” Riku finished with a nod.

“ _Incredible_ ,” Ienzo whispered.

“What?! Kairi’s not a princess anymore?!”

“I can’t believe we never figured it out,” said Ienzo.

“Yeah,” said Riku. “I don’t know how none of us noticed it happening. When did she give it up? She seemed to have it before the battle, right? Or, at least, I’m _pretty_ sure that’s what Master Yen Sid said.”

“Could she have--.”

               

Kairi, unbeknownst to the boys, had been standing in the distance behind them watching them. They huddled close together, practically shoulder to shoulder, holding something between them that she couldn’t see. Kairi glared. She clutched her hand in a fist over her heart. At first, a slow, crawling dry ice feeling spread through her body. It burned her insides. She gritted her teeth. Then, that feeling was replaced by fear as she realized what her body was unconsciously doing. She unclenched her fist and stared at it.

Her ears were filled abruptly with the sound of someone teleporting in behind her. She gasped and whipped around.

“Ah, my dear child. It seems that events have taken the turn I predicted, yes?”

Maleficent’s ghastly green visage came into view. She stroked the bulb on the end of her scepter as she gracefully glided out of the dark portal and moved towards Kairi. Reflexively, Kairi drew her blade.

“You again! Why are you here?! Leave me alone!!”

Maleficent smiled. “It is good to see you again too, young princess. Or should I say _ex_ -princess? Tell me, child, was it worth it?”

Kairi’s hands tightened on the hilt of her blade. “This is all _your_ fault, isn’t it?!” A pulse of dark energy flashed around her hands. She gasped. Her entire stance wavered.

“On the contrary. This is all _you_. I did warn you, didn’t I? You made your choice, and by casting off your pure light, you invited darkness. You shouldn’t be so afraid. You are finally simply a human. No longer a tool for someone else to use to extract power. You have agency now. You should use it.”

“This darkness _isn’t_ ‘agency,’ you hag! It’s puppetry! This is what happened to Riku! This is what killed Sora and everyone else I love! The darkness took _everything_ from me and I had to fight to get it all back, no thanks to you. I’ll destroy it and destroy you too!” More tendrils of dark energy erupted, but this time from around her entire body. Maleficent cackled.

“You would do well to be careful, Kairi. You don’t want your precious Sora or that ingrate Riku to see you like this now, do you?” Kairi gasped and looked over her shoulder. Sora and Riku were still huddled close, still not paying attention to her. “They’re already conspiring against you even as we speak, thinking of a way to be rid of you. You get in the way of their close friendship and your impure heart has made you useless to them.”

Kairi glared silently for a moment. Slowly, her anger melted into sadness and she hung her head. “It’s true, they are very close. And I can’t protect Sora like I’ve been able to before. I haven’t even told them yet.” She righted herself again. “But I don’t see why it should matter anyway! They may have a strong bond, but it doesn’t mean we aren’t friends! And friends are supposed to love me for who I am, not what I was.”

Maleficent cracked a grin. “If that’s what you believe, why don’t you run down the hill and tell them?”

Kairi’s lips parted and she released a shaking breath she didn’t know she’d been holding. Tears welled in her eyes.

“Why are you doing this to me?! What do you even want?!”

“You are again mistaken, my child. I am not the one causing this. You are. What you’re feeling right now, the anger, the fear, the doubt, the deliciously dangerous _envy_ , that comes directly from your own heart. I simply see a suffering girl and wish to lend her a hand. You cannot stand in the shadows and watch them forever. You will again have to make a difficult decision soon: reveal yourself, or let the darkness consume you? Join me, Kairi, and I will help you hone and control this new power in ways those fools will never be able to.”

“This again?! I already know about this routine from Riku! It’s not going to work on me.”

She smiled. “Very well. Today, you remain here. You are not yet ready, but when you are, I will know. Call for me and I will come to your aid.”

“I’ve had enough of this! I’m not doing anything with you. Go away!” She charged at Maleficent, but the witch evaded her. She teleported away in great green pillars of flame, her cackle echoing all around. Where she had stood, a card sat on the ground. Kairi put away her keyblade and bent down to pick it up. On the card were words in green text. It was a language she could read but not understand.

“Is this… a spell?”

“Kairi!! Are you okay?!”

She started. Sure enough, the loud, clumsy-sounding footsteps of Sora were approaching ever faster behind her. Quickly, she tucked the card away into a pocket and turned to face him.

“I’m okay Sora—woah!”

He wrapped his arms around her in a big bear hug. She chuckled and squeezed him back.

Riku, who had been running just behind him, chimed in. “We heard a commotion and saw you with your keyblade. Who was it? Are you hurt?”

Sora was practically crushing her now. She tapped on his back and feigned a cough to get him to release her a little. “It’s okay. It’s nothing. I was startled is all.”

Sora pulled back just enough to see her face. “Startled by what? Was it the Heartless?! Was it a NOBODY?!”

Kairi smiled and shook her head. “It was nothing. What are you two up to?”

Riku scrunched his eyebrows in scrutiny, but let his expression cautiously drop back into neutral.

“We were just on the phone with Ienzo,” said Sora. “We wanted the scientist’s take on your darkness thing!”

Kairi grimaced. “You talked to other people about it? People who weren’t there? Why would you do that?”

“Don’t worry. They’re good people, Kai! They’re going to help.” 

“We think you somehow managed to pass on the pure light you were guarding to a new keeper,” said Riku. “We can’t figure out how, when, or why, but the current theory is that it happened when you were knocked out. When the light was taken away from you, your heart became more normal.”

“And that means darkness!”

Riku nodded. Kairi clasped her hands together and looked away with a frown.

“That means it’s gonna be alright, Kairi,” Sora exclaimed with a huge grin. “We just have to figure out what caused you to start _feeling_ that darkness so we can help you control it! We’re gonna work through it with you!”

“It’s not going to be easy,” said Riku, “but if we can get to the bottom of this, that means you’ll be stronger and you’ll never have to go dark again. Not if you don’t want to.”

Kairi was deathly quiet.

“Well? What do you think, Kai?”

She looked first at Sora, then at Riku, and shook her head. She sighed deeply.

“I can’t even imagine what you must think of me right now.”

Sora frowned. “Think of you? What’s that mean?”

“All this time, all I’ve ever been good for is saving you with the light. Now that’s gone. If—no, _when_ another threat comes up, I’m going to fail you. And I won’t be able to save you. Who am I without that light?”

Sora and Riku exchanged worried glances.

“This is a lot worse than I expected,” Sora muttered to Riku.

“Hey, but she hasn’t let herself become possessed and destroyed the world yet. It’s not all that bad, all things considered,” Riku replied with a shrug.

Kairi’s eyes narrowed.

“Kairi… look, we know this isn’t what you expected,” said Riku. “We know this isn’t what you want, it’s not what _any_ of us want. But the alternative is to let this eat you and eat you until there’s nothing of you left. Don’t do that to us. Don’t do that… to _Sora_.”

He stared wistfully at his best friend. Sora was too fixated on Kairi to notice. He grasped her hands tightly once again.

“I’m going to be here with you no matter what. I made you that promise when we shared the fruit.” At that, Riku looked away and swallowed. “We can get through this _together_.”

Kairi couldn’t say anything, couldn’t think of anything to say. She simply nodded and let a tear fall down her cheek. Sora wrapped his arms around her once again. She sobbed into his jacket, gripping the fabric like it was the only thing standing between her and a 300-foot freefall.

“We don’t have to do anything about it today,” Riku said. He rubbed the back of his neck and made a point not to look directly at either of them. “In fact, um… maybe we—uh, _I_ should give you some time.”

Kairi lifted her head and nodded, then pulled back to look at Sora. “W-would you m-mind—would you mind coming home with me for a while?”

“Of course!”

She looked again at Riku. “You too?”

Riku shook his head no. “I don’t want to third wheel,” he said with a chuckle and a smile.

Kairi huffed a single half-hearted laugh. “I-if you’re sure?”

Riku nodded. “I’ll catch you two later, okay? If something happens, call me. I’m going to head home. Mom’s still not done giving me grief for the whole disappearing-for-a year-and-change thing anyway. She wants me home as much as she can get me.”

Sora grimaced. “Yeah… I know what you mean.”

Riku smiled and waved. “Seeya, lovebirds.”

“Bye Riku!”

He walked past them, smile dropping instantly as soon as they were behind him. He walked into the village, into his house, past his concerned mother, and into his bedroom. He collapsed on his bed face down and groaned loudly into his pillow.

**Notes for the Chapter:**

> And there we are! The first two chapters up! Yeehaw. I posted these two on the same day because... well, I could. It made sense in my head at the time. Whatever.
> 
> Just a note about how this story is going to flow. The first two chapters are pretty short, but they start to get longer and longer from this point on. Chapter 4 and the last chapter in particular are long as hell, but they're mostly filled with dialog so maybe they'll read fast? In other words... honey you got a big storm comin lol. This fic is over 20k because I don't know how to write anything under 20k, so plan accordingly...
> 
> On an unrelated note, I fucking love Ienzo. He's a good good sunshine boy. Every fic I write for KH from this point forward is always going to contain gratuitous Ienzo. He'll be back one more time in this fic. 
> 
> Alright, that about wraps it up. Seeya next week!


End file.
